Brown circles on underside of Chilli and Pepper plant

[food]

I am growing chilli and a pepper plant and both seem to have brown circles on the underside of the leaves. Also at the corner of the leaves they are drying up. Is this a fungal infection and is there anyway of treating it?

Thanks for any help given....

[momof4rugratz]

I can not help you but this is what am seeing on my banana pepper plant tonight